The present invention relates to a method for cephalometric imaging using an apparatus which comprises an X-ray source, a line detector camera equipped with a digital detector, which line detector camera is located to a position far away from the X-ray source for carrying out cephalometric imaging while the slot of the line detector camera is substantially vertical, whereby in cephalometric imaging, an X-ray beam located substantially on the vertical plane is directed from the X-ray source through the object being imaged, and the X-ray source is at the same time turned about the rotation centre located between the X-ray source and the line detector camera in order to scan the object being imaging in the horizontal direction, whereby the line detector camera is moved during the scanning movement in such a way that the ray beam meets the slot of the line detector camera. The publication U.S. Pat. No. 5,511,106 discloses this type of scanning method for cephalometric imaging.